I tend to always level way beforehand, and too much, so i might not be of much use here. in that case, i don't even know why i'm posting.

but anyways. my auron, and wakka were both doing 9999, and tidus was very close. they all had at least 5 or 6,000 health at that point. I never used Lulu, so I didn't bother putting her in that battle. The same goes for Rikku and Kimahri. Yuna had all of her spells except for Full-Life. I'm sorry, but I don't remember exactly what my stats were, except for strength, and hp. Auron and wakka each had around 80 strength, Tidus around 70, and yuna had a lot of mp.

But i'll say it again, I always love to make my battles a breeze, so I wouldn't go as far as I did unless you want to beat it in no time too.